Opposed piston combustion engines are known in the art. In such engines at least one common cylinder is provided having one piston arranged at each end. Two opposed pistons generally form a combustion chamber. When combustion takes place therein the gases act against both pistons driving them in opposite directions.
In general, opposed piston engines are provided with intake ports arranged near one end of the cylinder and exhaust ports arranged near the opposite end of the cylinder, each driven by the respective piston.
There are opposed piston engines having crankshafts or having power cams for transmission of power. The present disclosure relates to opposed piston engines having power cams for transmission of power.
Examples of such engines are disclosed in U.S. Pat. No. 5,551,383, EP0357291 and WO2005008038. Engines are disclosed comprising opposed pistons adapted to reciprocate in opposite directions and a main shaft carrying two power cams. The pistons are provided at their driving end with followers or bearings acting on the power cams. Reciprocation of pistons results in rotary motion of the main shaft.
In WO2010118457, for example, a pair of pistons is positioned to reciprocate in opposite directions along the longitudinal axis of the cylinder. A combustion chamber is defined between the pistons. First and second shafts are provided connected to respective axially spaced cams, and aligned to each other. In operation, the first shaft rotates continuously in the opposite direction to the second shaft. The second shaft has a longitudinal bore through which the first shaft can extend and rotate. This engine is not adapted to change its configuration when in use.
WO2012113949 filed in the name of the same applicant discloses an engine comprising a central hollow shaft and hollow arms projecting therefrom and connecting to respective cylinders each having opposing pistons defining a chamber therebetween. The engine further comprises two opposed power cams onto which bearings formed in the respective pistons roll to drive the engine.
The main advantage of these combustion engines is that side loads are eliminated or at least greatly reduced. However, the above prior art combustion engines are expensive, especially when different engines having different characteristics must be manufactured. In addition, said prior art combustion engines are high fuel consumption and poor performance engines.
There is therefore a need for providing opposed piston engines that can be easy to manufacture irrespective of whether they are engines with different characteristics to each other and with high performance and power.